The present invention relates to devices for intubating lacrimal ducts and more particularly to intubation sets for positioning a length of tubing in the lacrimal ducts.
The insertion of an elongate length of tubing member in the lacrimal ducts is a common surgical procedure for reconstruction or other remedial purposes. Lacrimal fluid or tears are continuously supplied from the lacrimal gland to wash across the sclera and other conjunctival components and the cornea. The excess lacrimal fluid is drained through a network of passages commencing with the puncta which appear as small papilla adjacent the inner canthus or inner corner of the eye, the lacrimal fluid being collected in the lacrimal sac by a number of canaliculi connecting the puncta with the lacrimal sac. The lacrimal sac is drained through the nasolacrimal duct which passes into the inferior nasal meatus. This network of passages is referred to hereinafter as the lacrimal ducts.
Closures of the lacrimal ducts can occur as a result of congenital anomalies, accidents, inflammation, advanced aging, as well as other physiological conditions. The closures prevent drainage of tears so that the affected eyes are continually brimming over with fluid, causing much personal discomfort to the patient, and often causing infection and/or inflammation of the mucous membranes as well as other undesirable conditions.
Known devices for correcting blocked lacrimal ducts include an intubation set disclosed in U.S. Pat. No. 4,380,239 to Dr. John Crawford, et al. The intubation set includes a probe consisting of a light resilient wire which can be readily deflected through an angle of at least 90 degrees to permit the probe to pass from the nasolacrimal duct to the inferior nasal meatus. The probe has a tip or distal end which is slightly enlarged and rounded to limit the possibility of damage to tissue when the probe is inserted, and a proximal end provided with an enlargement. A very flexible tube of minimal rigidity has a first end which is in engagement over the wire at the proximal end and into contact with the enlargement. Adhesive can be used to improve the connection.
When in use, the probe is inserted through either an upper punctum or a lower punctum of the lacrimal ducts and is guided downwardly through the lacrimal ducts to the inferior nasal meatus whereupon a tool in the form of a hook (shown in the Crawford patent) is used to pull the probe through the nostril leaving a length of tubing extending through the full length of the lacrimal ducts.
Although the Crawford intubation set provides a relatively secure connection between the tube and the probe, in rare instances these components have been found to separate during the intubation procedure. The cause is believed to be contact with bony structure which tends to roll the tube off the wire. Although this event is unusual, it would be preferable to provide an intubation device which benefits from the principles taught in the Crawford patent and which also has a connection between the probe and the tube which is less likely to suffer from this problem.
It is also possible for a closure to occur in the canaliculi and not in the nasolacrimal duct. For instance, the canaliculi may suffer traumatic injury while the nasolacrimal duct remains unaffected. It is therefore also desirable to provide an intubation set adapted to position a length of tubing in the region of the canaliculi without probing the healthy nasolacrimal duct in order to facilitate intubation by a physician.
In accordance with an aspect of the invention, an intubation set is provided having an improved connector between a tube and a probe. In a preferred embodiment, the connector includes a deformable sleeve which at one end receives an end of the tube and at the other end is tapered to converge on the probe where it it is permanently attached. The tube contains a solid insert which can be set in a compound such as silicone rubber and the sleeve is deformed radially inwardly to trap part of the tube containing the insert thereby locking the tube to the sleeve and hence to the probe. A method of making the intubation set is also provided.
The invention also provides an improved intubation set for use in intubating the canaliculi without probing a healthy nasolacuimal duct. In this case the probe is bent into a predefined spiral configuration and preferably lies in a plane. A tip on the probe can be pulled out of the plane to create a spiral for easier insertion. The spiral can be clockwise or anticlockwise depending on which way the tip is pulled out of the plane.
These and other aspects of the invention will be better understood with reference to the following description and drawings.